Ignition Coil Power Source
WARNING: This page is about a different car, the 1998 GMC Pickup, 1998 GMC Cab & Chassis, 1998 Chevrolet Pickup, and 1998 Chevrolet Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
Turn ignition on. Check ignition positive voltage circuit of ignition control module for battery voltage. See WIRING DIAGRAMS - 6.5L DIESEL article. If battery voltage is not present, check ignition or ECM 1 fuse. If fuse is not blown, check for open between fuse and ignition control module.